Ignition system for petroleum burning instrument

ABSTRACT

An ignition system for petroleum burning instruments is provided which comprises an ignition nozzle for injecting an ignitable fuel towards a subject being ignited, an air compression pump for supplying compressed air to the nozzle to operate the nozzle, and a pair of discharge electrodes arranged in front of the nozzle in opposite relation to each other. The pair of electrodes form an airgap thereacross through which a jet flow of the ignitable fuel passes, and are connected across a piezoelectric transducer for inducing a spark, by discharge, across the airgap to thereby ignite the ignitable fuel in response to the actuation of the transducer. The transducer is mechanically impacted by separate means in response to a predetermined operative position of the pump.

United States Patent Inventor Keniiro Goto Tokyo, Japan Appl. No. 17,377 Filed Mar. 9, 1970 Patented Nov. 23, I971 Assignee Mansei Kogyo Kabushlki Keisha Kawaguchi-shi. Japan Priorities June 14, 1969 Japan 44/56382;

July 12, 1969, Japan, No. 44/66224 IGNITION SYSTEM FOR PETROLEUM BURNING INSTRUMENT 20 Claims, 9 Drawing Figs.

US. Cl

Int. Cl Field of Search 431/255, 317/81 F23q 3/00 431/255; 123/148 BA; 317/81 Primary Examiner- Edward G. Favors AnorneySaul Jecies ABSTRACT: An ignition system for petroleum burning instruments is provided which comprises an ignition nozzle for injecting an ignitable fuel towards a subject being ignited, an air compression pump for supplying compressed air to the nozzle to operate the nozzle, and a pair of discharge electrodes arranged in front of the nozzle in opposite relation to each other. The pair of electrodes form an airgap thereacross through which a jet flow of the ignitablc fuel passes, and are connected across a piezoelectric transducer for inducing a spark, by discharge, across the airgap to thereby ignite the ignitable fuel in response to the actuation of the transducer. The transducer is mechanically impacted by separate means in response to a predetermined operative position ofthe pump.

PIEZOE- IMPACT I DISCHARGE LECTRK; :GENERATING ELECTRODE TRANSDUCER DEVICE l I 21 3L s ffig IGNITION COMPRESSION IGNITED 1 NOZZLE PUMP i I r5 1 Q l 1 DISCHARGE DRIVE I ELECTRODE 1 MEANS l 1 i I PATENTEDuuv 23 IEIII SHEET 1 [IF 4 FIG.

IMPACT GENERATING DEVICE COMPRESSION PUMP DRIVE MEANS PIEZOE- TRANSDUCER DISCHARGEv LECTRIC ELECTRODE IGNITION NOZZLE DISCHARGE ELECTRODE SUBJECT BEING V IGNITED FUEL TANK FIG. 2

Inventor Kcnjiro Goto IGNITION SYSTEM FOR PETROLEUM BURNING INSTRUMENT The invention relates to an ignition system for petroleum burning instruments, and more particularly to an improvement of such an ignition system which utilizes an instantaneous spark produced by electric discharge as its ignition source.

In one type of petroleum burning instruments, the burning of petroleum takes place through the medium of a fiber wick, and in another, atomized petroleum is adapted to be burned directly without resource to such medium. The former mode is widely employed in general purpose instruments such as Reroseue stoves or petroleum cooking stoves, while the latter finds its principal applications in industrial burners. Because of the inconvenience which is experienced with the starting of petroleum burning instruments as compared with electrical heaters, it is the most important task imposed on such burners to ensure that they are ignited in a safe and positive manner.

The use of an electrical heater to provide ignition of materials to be fired, that is, either fuel absorbent fiber wicks or atomized fuel, is well known. For example, a filament resister is located within or adjacent materials which are to be fired (herein after referred to as a subject being ignited) and connected for electrical energization. This undoubtedly is a construction, and when the filament subjected to red heat, will provide a positive action on the material unless the filament fails. However, because of the fact that the filament is exposed in use to elevated temperatures all during the operation of the burner, this method inherently involves the disadvantage of a high failure rate. In addition, the power supply to the filament resister should not be derived from external sources, particularly for home appliance burners, and this necessitates the use of a battery, which requires replacement.

An ignition system which is operable based on a spark or sparks produced by electric discharge is also known. The system is provided with a pair of discharge electrodes in place of the filament resistor, but the instantaneous spark produced across the electrodes is insufficient to successfully ignite a certain kind of material to be fired, such as fiber wick, so that the instrument of this type must be usually provided with an igniter which is adapted to be fired by the spark. Though the duration of the discharge is almost instantaneous, the system also still suffers from the trouble of limited battery life. Further, and more important, petroleum which is a hydrocarbon compound containing organic acids, sulfur and nitrogen compounds does not have such a high inflammability as would be ignited without when atomized into the atmosphere. Hence, there remains the problem of assuring positive ignition. Where the ignition process is repeated due to one or more failures, or where there is a delay between commencement of the atomizing operation and the ignition, there arises the risk that the atomized fuel which has been supplied in the interval may give rise to an explosive combustion. In order to ignite the atomized fuel with an instantaneous discharge spark, it is necessary that the discharge timing be properly established and maintained in relation to the jet flow rate and diffusion area of fuel as well as the mixture ratio of the fuel and air. The prior art ignition system failed to produce the discharge at the optimum time for the ignition of the fuel is suitable because of the failure to control the time relationship between the fuel atomization and the discharge.

Therefore, it is a general object of the invention to provide an ignition system for petroleum burning instruments which completely overcomes the aforesaid disadvantages of the prior art.

It is a specific object of the invention to provide an ignition system for petroleum burning instruments in which an ignitable fuel is atomized towards a subject being ignited, and is ignited by discharge means which is responsive to the atomizing process to produce an instantaneous spark at the optimum ignitable moment during the atomizing process, and which maintains the combustion of the subject being ignited until the latter is fully ignited.

Another object of the invention is to provide an ignition system for petroleum burning instruments which is simple in construction, facilitates handling, and uses a dischargeproduced spark as ignition source without requiring an external electric power supply or battery.

In accordance with the invention, there is provided an ignition system for petroleum burning instruments which comprises a mechanical air compression pump, an ignition nozzle cooperating with the pump for drawing and atomizing an ignitable fuel towards a subject being ignited during the discharge operation of the pump, a pair of discharge electrodes positioned in front of the ignition nozzle and capable of igniting the atomized issuing fuel therefrom, a piezoelectric transducer electrically connected across the discharge electrodes, and means responsive to one operative position of the pump during the discharge operation thereof for generating mechanical energy to be imparted as an impact to the piezoelectric transducer.

Thus, according to the invention, during the atomizing process at the ignition nozzle, said impact generating means is made responsive to one operative position of the pump at which the ignitable fuel reaches the condition of optimum inflammability, to operate the piezoelectric transducer so as to produce an electric energy of high potential which is applied across the pair of electrodes, thereby causing a discharge thereacross, with the resulting instantaneous spark reliably igniting the fuel.

The above and other objects, features and advantages of the invention will be more fully understood from the following description of several embodiments thereof, taken together with the drawings, in which FIG. 1 is a block diagram of ignition system for petroleum burning instruments according to the invention.

FIG. 2 is an illustrative time diagram of the atomizing process for an ignitable fuel issuing from the ignition nozzle shown in FIG. 1.

FIG. 3 is a schematic section, partly cut away and simplified, of an ignition system according to the invention.

FIG. 4 illustrates the flow control tube shown in FIG. 3, in its operating condition.

FIG. 5 is a graph indicating the amount of air in the atomized fuel, drawn to show the characteristic of the flow control tube.

FIG. 6 is a section of an improved air compression pump.

FIG. 7 is an elevation, partly in section, of an improved impact generating device.

FIG. 8 is a schematic section of a modification of the embodiment shown in FIG. 3, and

FIG. 9 is a schematic section of a further embodiment of an ignition system according to the invention which is similar to the embodiment of FIG. 8 except that an operative lever is axi ally movable.

Referring to the drawings, and particularly FIG. I, there is shown an ignition system for petroleum burning instruments according to the invention. In this figure, several different kinds of lines are used to show various systems, and specifically the fuel system is represented by dotted lines, the electrical system by chain lines, the pneumatic system by a single solid line, and the mechanical system by double solid lines. As will be apparent from this figure, the system includes a subject being ignited, identified with reference numeral 1, towards which is atomized an ignitable fuel from an ignition noule 2, as indicated by an arrow. The nozzle 2 is connected with an air compression pump 3 and operable to draw the ignitable fuel therein with the discharge operation of the pump 3 and to atomize it into the air. The ignitable fuel may be kerosene as is the main fuel and hence a fuel tank 4 is desirably shared by both fuels. The air compression pump 3 is a so-called reciprocating pump which may be of either bellows or piston type. The pump is adapted to be driven by a suitable drive means 5 which is properly selected depending upon the type of the pump. Because the air compression pump 3 is of reciprocating type, it will be appreciated that the nozzle 2 atomizes the ignitable fuel is response to each discharge operation of the pump 3. In other words, one discharge stroke of the pump 3 corresponds to one atomizing process. As a result, it will be seen that the optimum inflammable condition during a single atomizing process corresponds to one operative position of the pump during its discharge operation.

A pair of discharge electrodes 6 are arranged in front of the outlet port of the nozzle 2 so that the ignitable fuel from the latter can pass through the air gap between the electrodes. These electrodes are electrically connected with a piezoelectric transducer 7, and the arrangement is such that when the piezoelectric transducer produces electrical energy, a spark is induced across the discharge gap to ignite the fuel that is atomized by the nozzle 2 towards the subject being ignited 1. Of course, the spark will be ineffective or as an ignition source unless it occurs during the atomizing process of the ignitable fuel, and in accordance with the invention the timing of this discharge is controlled so as to be responsive to the optimum inflammable condition of the ignitable fuel during the atomizing process, as will be more fully described later. As is well known, a piezoelectric transducer produces an electrical energy proportional to the amount of stress applied thereto, and consequently it is possible to derive a high voltage by impressing the transducer with a high mechanical energy. Electrical energy of substantially high voltage is needed for the arrangement which is used to induce a spark across the discharge gap, and hence the piezoelectric transducer 7 is associated with an impact generating device 8. According to the invention, the device 8 is connected with the pump 3 to be driven bythe drive means together with the latter, and is controlled thereby to be operative in response to one operative position of the pump during its discharge operation. Thus the device 8 responds to the one operative position, during the discharge stroke, of the pump which corresponds to the optimum inflammable condition of the ignitable fuel during the atomizing process, and imparts an impact to the piezoelectric transducer 7 at such moment. This results in the production of a spark across the discharge gap formed by the pair of electrodes 6, whereby the ignitable fuel which is passing through the gap is positively ignited.

F IG. 2 is a time diagram showing the atomizing process for the ignitable fuel which takes place with the ignition system of the invention. It should be noted that the division of time segments is not indicated precisely to actual processes. The arrow shown indicates the elapse of time, and the length of each block represents the required time length. In this figure, point A denotes the position in time at which the discharge operation of the air compression pump commences, point B the start of atomization of the ignitable fuel, point C the discharge, that is the ignition of the fuel, point D the ignition of the subject being ignited, and point E the termination of discharge of the air compression pump, namely the termination of atomization of the ignitable fuel. As will be apparent, during the interval between points A and B, no ignitable fuel is atomized, but only the air is ejected. This represents the time interval taken by the ignitable fuel to reach the nozzle from the fuel tank, it being obvious that no ignition is possible during this interval. During the subsequent interval from point B to point E, the ignitable fuel is ejected together with the compressed air, and hence the ignition may be possible at this stage. However, at positions in time adjacent point B, there will be an excess of ambient air surrounding the ignitable fuel, which means a condition of poor inflammability. The ignition is advantageously effected at point C which is situated a suitable time period after point B. this being particularly advantageous for that kind of subject being ignited which is similar to a fiber wick since the latter is supplied with the ignitable fuel by that time and hence in a condition susceptible to inflammation. In other words, point C represents the optimum inflammable condition of the ignitable fuel. Subsequent to the ignition at point C, the combustion continues until point E, and in the meantime the subject being ignited fires at point D. Thus in the interval between point D and point E, the subject being ignited undergoes combustion together with the ignitable fuel, which assures a reliable ignition of the subject being ignited.

PEG. 3 shows an ignition system of the invention as applied to a kerosene stove having a fiber wick. In FIG. 3, part of the ignition system is shown as removed from the body of the kerosene stove for convenience of illustration, but in practice it will be situated suitably within the body.

Variousforms of kerosene stoves are known, but the stove particularly shown is of the type in which the wick is raised and lowered. Referring to FIG. 3 more specifically, there is provided a fuel tank 1 l for storing kerosene. The tank carries an outer wick sleeve 12 on its top wall and also carries an inner wick sleeve 13 on its bottom wall. Both sleeves l2 and 13 extend upwardly from the tank 11 in concentric manner and have flanges 12a and 130, respectively, at their upper ends, which support a burner assembly 14. The burner assembly 14 is also concentrically arranged, and comprises an inner cylinder 16, an outer cylinder 17 and their surrounding cover 18 which are connected together by an interconnection bar 15. The assembly 14 further includes a top situated, heat radiant meshwork 19. lnterrnediate the inner and outer wick sleeves 12 and 13 is placed a burning fiber wick 20, which is held in place by a wick holding unit (not shown), only the retaining ring 21 of the unit being shown in FIG. 3. The fiber wick 20 has its bottom part immersed in the kerosene contained in the fuel tank 11, and becomes combustible by absorption of the fuel. Normally the top end of the fiber wick 20 extends through the space between the inner and outer sleeves l2 and 13 into the space between the inner and outer cylinders 16 and 17 for combustion. When the fiber wick is retracted again into the space between the inner and outer sleeves 12 and 13, the fire extinguishes itself automatically. For this purpose, the illustrated stove requires raising and lowering of the fiber wick 20, which is effected in the example shown by a raising and lowering adjusting unit having a shaft 23 attached with a knob 22. Because the construction of such unit is well known, it is not shown in detail. Generally, the

'wick raising and lowering adjusting unit is operatively connected with the wick retaining unit.

In accordance with the invention, the cover 18 and the outer cylinder 17 of the burner assembly 14 are formed with aligned windows 24, respectively, and an ignition nozzle assembly generally shown at 25 is disposed outside the cover 18 so as to be opposite the windows 24. The nozzle assembly 25 is supported by a bracket 26 mounted on the fuel tank 11. The noule assembly 25 comprises an injection tube 28 having an outlet port 28 for the compressed air, an enclosure member 30 which covers the injection tube 28 and has an outlet port 29 aligned with and arranged in front of the outlet port 27 of the injection tube 28, a fuel suction pipe 32 having an outlet port 31 which opens into the sidewall of the enclosure member 30, and a flow control tube 33 mounted on the outlet end of the enclosure member 30 and extending forwardly therefrom. The forward end of the flow control tube 33 is arranged in abutting engagement with the wall of the window 24 formed in the cover 18 of the burner assembly 14, so that the outlet port 29 of the enclosure member 30 is disposed opposite the fiber wick 20 in its burning position, communicating with the wick through the two windows 24. The fuel suction pipe 32 is connected with one end of a piping 34 whose other end is located within the fuel tank 11. The injection tube 35 is connected with one end of a piping 35, the other end of which is coupled with an air compression pump 36. With this arrangement of the nozzle assembly 25, compressed air is discharged through the outlet port 27 of the injection tube 28 as the pump 36 operates, and then the reduction of pressure within the enclosure member 30 causes fuel (ignitable fuel) to be drawn therein from the fuel tank 11 through the fuel suction pipe 32. As a result, the ignitable fuel will be ejected together with the compressed air towards the fiber wick 20 positioned in the burning position, through the flow control tube 33 and the windows 24. The action of the flow control tube 33 will be described later more fully.

In FIG. 3, the air compression pump 36 is shown to be installed as an independent component, but it will be understood that desirably the pump is mounted on the stove body or on the fuel tank 11. The pump 36 incorporates bellows 37 for reciprocating motion. At one end, the bellows 37 includes a suction inlet 37b having a valve 37a, and a discharge port 37c. The discharge port 37c is connected with the piping extending from the injection tube 28. The other end of the bellows 37 is in driving engagement with a pivotable arm 38, this end serving as a driving end 37d. The bellows 37 is enclosed in a casing 39 which is constructed to assure a proper motion of the bellows 37. The driving connection between the pivotable arm 38 and the bellows 37 is permitted by a slot 39a in the casing 39. As the pivotable arm 38 moves angularly, the bellows 37 contracts and expands lengthwise, thereby operating as a reciprocating pump. The pivotable am 37 is fixedly mounted on an operating shaft 40 which is adapted to be driven by the rotation of a knob 41. Thus the operation of the knob 41 operates the pump 36, with consequent ejection of the compressed air and the ignitable fuel from the nozzle assembly 25.

Accordingly to the invention, a pair of discharge electrodes 42 and 43 are arranged in the wall of the flow control tube 38 so as to be opposite each other for igniting, in the interior of the tube 38, the ignitable fuel which is ejected from the outlet port 29 of the enclosure member 30 by means of a spark that is induced across the airgap between the electrodes. The pair of discharge electrodes 42 and 43 are electrically connected with a power supply which comprises a piezoelectric transducer 44, and subjected to discharge with the production of an instantaneous voltage by the transducer. The piezoelectric transducer 44 is surrounded by an electrically insulating material 45 and is placed within a housing 46 so as to be opposite a hammer 47 which can impart a mechanical impact upon the transducer. A coiled spring 48 is also placed in the housing for resiliently urging the hammer 47 in a direction to abut against the piezoelectric transducer 44. The hammer 47 is secured with a pin 49 which projects externally of the housing 46, the latter being formed with an elongated slot 50 for allowing axial movement of the pin 49. The pin 49 is normally in operative engagement with an arm 51 that is pivoted to the free end of a pivotable arm 52 adjacent a stop 53 provided thereon, the stop 53 preventing the rotation of the arm 51 in the reverse direction. The pivotable arm 52 is fixed on the same operating shaft 40 as the pivotable arm 38 coacting with the pump 36, and is rotatable with the shaft. As a consequence, when the knob 41 is operated, the hammer 47 moves, as the pivotable arm 52 moves angularly, axially towards the spring 48 against the urging action thereof by virtue of the engagement between the second am 51 and the pin 49, and as the pivotable arm 52 further moves angularly, the second arm 51 will be moved out of engagement with the pin 49, whereupon the hammer 47 is released and forced by the coiled spring 48 to strike the piezoelectric transducer 44 with an impact. The resulting electromotive force produced in the transducer 44 induces a spark across the pair of discharge electrodes 42 and 43.

From the foregoing description, it will be seen that both the air compression pump 36 and the impact generating means 47 operate with the rotation of the common operating shaft 40. This is accomplished by way of the two pivotable arms 38 and 52 fixed on the operating shaft 40. More specifically describing the operation, as soon as the discharge from the air compression pump 36 commences, the coiled spring 48 for the impact generating means begins to be compressed. While the discharge from the air compression pump 36 will immediately cause an ejection of compressed air from the nozzle 25, the draw of the ignitable fuel will involve a time delay correspond ing to the passage of fuel from the fuel tank 11 to the outlet port 31 of the fuel suction pipe 32. As a result, there will be a time period that elapses from the commencement of the operation of the air compression pump 36 until the optimum ignition condition is reached in the nozzle 25. During this time interval, the coiled spring 48 continues to be compressed. and

it will be appreciated that it is possible to make the discharge coincident in time with the optimum ignition condition if the spring 48 is released at the time when such condition is reached. As a matter of practice, if the arrangement is such that the optimum ignition condition occurs immediately after the pump 36 has commenced to operate, the mounting angle of the pivotable anns 38 and 52 can suitably be adjusted so that the compression of the spring 48 is advanced to ensure a proper operation of the impact generating 15 means 47. A similar remedy is provided for the reverse occasion. Since the drive to the pump 36 can be continued after the release of the impact generating means 47, it is possible to maintain the flame once created in the nozzle 25. In this manner, the ignition system shown can provide an ignition at the optimum ignition condition and maintain the resulting flame, thereby reliably igniting the subject being ignited or the fiber wick.

FIGS. 4 and 5 illustrate the function of the flow control tube 33 in the nozzle assembly 25. It is recognized that generally when a fuel is ejected from a thin nozzle, the fuel is strongly diffused as it leaves the outlet port so that the excess of the amount of air present with respect to the fuel causes ignition difficulties. To overcome this, according to the invention, the flow control tube 33 is disposed in front of the outlet port 29 as mentioned previously. The flow control tube 33 suppresses the diffusion of the ignitable fuel as it is atomized through the outlet port 29 and controls it, to provide a jet flow oriented in a definite direction. It also serves to maintain a constant amount of air therein. As shown in FIG. 5 in which the abscissa represents the distance from the outlet port 29 and the ordinate the amount of air, the amount of air will be maintained constant for the range from the outlet port 29 to the free end of the flow control tube 33. A pair of chain lines shown in FIG. 5 indicate the extent of an optimum amount of air. Consequently, when the ignitable fuel containing an optimum amount of air is ejected from the outlet 29, there will be no further ingress of air into the flow control tube 33, which therefore assures a stable ignition.

FIG. 6 shows a modified air compression pump from that shown in FIG. 3. In this pump, a pressing member 54 is arranged adjacent the driving end 37d of the bellows 37. The pressing member 54 is held in place by a spring plate 55 mounted in the form of a diaphragm within the casing 39, and acts to force the driving end 37d of the bellows 37 by the resilient force that obtains upon reversal of the spring plate. The pressing member 54 is attached with a pin 56 that projects externally of the casing 39. The pin 56 engages a notched groove 58 in a rotatable wheel 57 which can rotate with the operating shaft 40, As a consequence, when the wheel 57 rotates clockwise as viewed in FIG. 6, the engagement of one end of the notched groove 58 with the pin 56 causes the pressing member 54 to be urged towards the bellows 37, against the action of the resilience of the spring plate 55, and upon reversal of the spring plate 55 the member 54, releasing the operative engagement of the pin 56, is forced against the bellows 37 by the flipping action of the spring. When the wheel 57 is rotated counterclockwise, the pin 56 is engaged by the other end of the notched groove 58, and the member 54 is urged away from the bellows 37 against the resilient action of the spring and is reset or assumes its original position upon the reversal of the spring plate 55, this reversal being in the opposite direction from the first mentioned reversal.

The advantage of such a resiliently driven pump is found in the fact that it automatically maintains the drive to the pump which may be interrupted with manual dn've upon ignition, irrespective of the subject being ignited not yet being ignited in fact, and thus maintains the flame produced by the nozzle assembly until the subject being ignited has actually been ignited. It will be seen that in FIG. 6, the bellows 37 may be replaced by a piston and cylinder arrangement.

FIG. 7 shows the use of a diaphragm shaped spring plate 59 similar to that shown in FIG. 6 for the impact generating means. Thus the arrangement is changed in that the piezoelectric transducer 44 is substituted for the bellows 37 in a position opposite to the hammer 47. The hammer 47 is held in place by the spring plate 59 which is mounted within the housing 46 in the form of a diaphragm, and resiliently strikes the piezoelectric transducer with an impact upon reversal of the spring. The hammer 47 is similarly provided with the pin 49 which projects externally of the housing 46, and is similarly controlled by the pin 49 as was mentioned before in connection with the pin 56. However, in the present instance, it is necessary to release the operative engagement of the pin 49 upon the reversal of the spring 59, therefore the pin 49 engages a notched groove 6ll in rotatable wheel 60 mounted on the operating shaft 40, in a similar manner as does the pin 56 of FIG. 6. The use of a diaphragm shaped as spring plate 59 removes the necessity of the release control for the coiled spring as shown in FIG. 3, thereby enabling to simplify the construction. In addition, there is provided a correct control over the commencement of the drive to the hammer 47, so that the control of producing the discharge in response to the optimum ignition condition is facilitated.

FIG. 8 shows another embodiment of the ignition system according to the invention which employs a modified operating means from that of previous embodiments. In this figure, parts corresponding to the previous embodiments are denoted by same numerals as used before. The feature of the improved operating means is the use of a rockable operating lever 62 pivoted at one end 61, instead of the operating shaft previously mentioned. The operating lever 62 has a knob 63 mounted at its other end, the knob being moved to the right and the left as viewed in FIG. 8 for rocking motion. Two elongate slots 64 and 65 are formed lengthwise in the operating lever 62 and operatively connected with links 66 and 67, respectively, at respective pivot 68 and 69. It will be seen that the rocking motion of the operating lever 62 results in the lengthwise movement of the links 66 and 67 along the respective slots. Adjacent the other end, the first link 66 has a slot 70 formed therein, which is operatively engaged with the impact generating means 70, which is quite similar to that shown in FIG. 7. Thus the pin 49 associated with the hammer 47 engages the slot 70 in the first link 66. On the other hand, the second link 67 has its other end operatively connected directly with the air compression pump 36. The pump 36 shown is similar to that shown in FIG. 3. If required, the other end of the second link 67 may be formed with a slot, as is provided in the first link 66, which can be engaged with a resiliently driven pump as shown in FIG. 6. The use of the rockable operating lever 62 does not change the control over the operational relationship between the air compression pump 36 and the impact generating means 47.

FIG. 9 shows a further embodiment of the ignition system according to the invention which was still further different operating means. The improved operating means comprises an axially movable operating rod 71, which drives and controls the air compression pump 36 and the impact generating means 47. The operating rod 71 includes a pair of arms 72 and 73. The first arm 72 is formed at its end with an elongate slot 74 which extends parallel to the operating rod 7!, the slot 74 being operatively engaged with the pin 49 of the impact generating means 47 in the similar manner as shown in FIG. 8. The second arm 73 has its end operatively connected with the air compression pump 36 as was shown in FIG. 8. Consequently, the axial movement of the operating rod 71 causes the drive to be imparted to the impact generating means 47 and the air compression pump 36 from the first and second arms 72 and 73, respectively. In this instance, the control over the operational relationship between them is similarly provided as mentioned previously.

While the invention has been described in detail with reference to several particular embodiments of petroleum burning instruments, further changes and modifications of the disclosed construction will be possible to those skilled in the art without departing from the spirit of the invention. Therefore, it is intended that the embodiments described are only illustrative and not limiting of the scope of the invention.

Having described the invention, what is claimed is:

1. An ignition system for petroleum burning instruments comprising an ignition nozzle for ejecting an ignitable fuel towards a subject being ignited; an air compression pump of reciprocating type for supplying compressed air to the nozzle to thereby operate the nozzle; a pair of discharge electrodes arranged in front of the nozzle and defining with one another an airgap through which passes a jet flow of the ignitable fuel; a piezoelectric transducer electrically connected across the discharge electrodes for applying a discharge voltage thereacross so that a spark discharge is induced across said air gap to ignite the ignitable fuel of said jet flow; impact generating means operatively connected with a drive source for energizing the piezoelectric transducer upon operation of the source; and operating means for driving said pump and being responsive to one operative position of the pump in the compression stroke of the same to operate said impact generating means, and also being responsive to another operative position of the pump in the suction stroke of the same to reset the impact generating means.

2. An ignition system according to claim I in which said engaging means comprises a pin provided on a driving end of the air compression pump, and a wheel having an elongate notched groove in which the pin engages, said wheel being angularly movable so as to impart an angular motion to the notched groove and being operatively connected with the operating means to move the pin releasably in the driven direction of the pump.

3. An ignition system according to claim 1, in which said air compression pump comprises bellows and operates by expansion and contraction of the bellows.

4. An ignition system according to claim 1, in which the air compression pump comprises engaging means for operatively connecting the pump with said operating means, and a diaphragm operable to move from an inoperative to an operative position by the operation of said operating means and concurrently to release said engaging means, thereby resiliently driving the pump, said diaphragm being capable of being operated and reset by said operating means through said engaging means.

5. An ignition system according to claim 4, in which said engaging means comprises a pin provided on a driving end of the air compression pump, and a lever having an elongate slot in which said pin engages, said lever being movable lengthwise of the slot and being operatively connected with said operating means to move the pin releaseably in the driven direction of the pump.

6. An ignition system according to claim 1, in which said impact generating means comprises a hammer which strikes the piezoelectric transducer, a spring which resiliently drives the hammer, and engaging means for operatively connecting the spring with said operating means and/or for releasing the connection between the spring and the operating means.

7. An ignition system according to claim 6, in which said spring comprises a coiled spring which resiliently urges the hammer in a direction to strike said piezoelectric transducer, said engaging means being operable by the operation of said operating means to separate the hammer from the piezoelectric transducer against the resistive force of the coiled spring and to release the hammer.

8. An ignition system according to claim 7, in which said coiled spring has an axis directed to the piezoelectric transducer, said hammer being connected to move on said axis.

9. An ignition system according to claim 7, in which said engaging means comprises a pin projecting from the hammer, a pivotable arm, a second arm pivoted to said pivotable arm and normally engaging said pin, and a stop secured to the pivotable ann adjacent said second arm, said pivotable arm being operatively connected with said operating means to move angularly so as to release said pin after said second arm has moved said pin in a definite direction.

10. An ignition system according to claim 6, in which said spring comprises a diaphragm which holds the hammer movable in a direction to strike the piezoelectric transducer, said engaging means being operable by the operation of said operating means to drive the hammer to the operative position of the diaphragm and to release the hammer.

11. An ignition system according to claim 10, in which the diaphragm has a center axis directed towards the piezoelectric transducer and holds the hammer on the center axis.

12. An ignition system according to claim 10, in which the engaging means comprises a pin projecting from the hammer, and a lever having an elongate slot in which said pin engages and is movable lengthwise of the slot, the lever being operatively connected with said operating means to move said pin releaseably in the driven direction of the hammer.

13. An ignition system according to claim 10, in which said engaging means comprises a pin projecting from the hammer, and a wheel having an elongate notched groove in which said pin engages and is angularly movable to impart an angular motion to said notched groove, the wheel being operatively connected with said operating means to move said pin releasably in the driven direction of the hammer.

14. An ignition system according to claim 1, in which said operating means comprises an angularly movable operating shaft which is connected with and drives the air compression pump and the impact generating means, respectively.

15. An ignition system according to claim I, in which said operating means comprises a pair of links connected with the nected with the respective links for driving the air compression pump and the impact generating means.

16. An ignition system according to claim 1, in which said operating means comprises a pair of arms operatively connected with the air compression pump and the impact generating means, respectively and an axially movable operating rod connected with said arms for driving the air compression pump and the impact generating means.

117. An ignition system according to claim 1, in which the ignition nozzle comprises an injection tube having an outlet port for compressed air, and an enclosure member for covering the injection tube at a distance therefrom, the enclosure member having an outlet port positioned in front of the outlet port of the injection tube and having a suction inlet port for an ignitable fuel in the side wall thereof.

18. An ignition system according to claim 1, in which said ignition noule includes an injection flow control tube mounted forwardly of the outlet end thereof.

19. An ignition system according to claim 18, in which said injection flow control tube is made from an electrically insulating material.

20. An ignition system according to claim 19 in which said injection flow control tube made from an electrically insulating material has a pair of discharge electrodes disposed within air compression pump and the impact generating means,

respectively, and a rockable operating lever operatively conil '0 k 

2. An ignition system according to claim 1 in which said engaging means comprises a pin provided on a driving end of the air compression pump, and a wheel having an elongate notched groove in which the pin engages, said wheel being angularly movable so as to impart an angular motion to the notched groove and being operatively connected with the operating means to move the pin releasably in the driven direction of the pump.
 3. An ignition system according to claim 1, in which said air compression pump comprises bellows and operates by expansion and contraction of the bellows.
 4. An ignition system according to claim 1, in which the air compression pump comprises engaging means for operatively connecting the pump with said operating means, and a diaphragm operable to move from an inoperative to an operative position by the operation of said operating means and concurrently to release said engaging means, thereby resiliently driving the pump, said diaphragm being capable of being operated and reset by said operating means through said engaging means.
 5. An ignition system according to claim 4, in which said engaging means comprises a pin provided on a driving end of the air compression pump, and a lever having an elongate slot in which said pin engages, said lever being movable lengthwise of the slot and being operatively connected with said operating means to move the pin releaseably in the driven direction of the pump.
 6. An ignition system according to claim 1, in which said impact generating means comprises a hammer which strikes the piezoelectric transducer, a spring which resiliently drives the hammer, and engaging means for operatively connecting the spring with said operating means and/or for releasing the connection between the spring and the operating means.
 7. An ignition system according to claim 6, in which said spring comprises a coiled spring which resiliently urges the hammer in a direction to strike said piezoelectric transducer, said engaging means being operable by the operation of said operating means to separate the hammer from the piezoelectric transducer against the resistive force of the coiled spring and to release the hammer.
 8. An ignition system according to claim 7, in which said coiled spring has an axis directed to the piezoelectric transducer, said hammer being connected to move on said axis.
 9. An ignition system according to claim 7, in which said engaging means comprises a pin projecting from the hammer, a pivotable arm, a second arm pivoted to said pivotable arm and normally engaging said pin, and a stop secured to the pivotable arm adjacent said second arm, said pivotable arm being operatively connected with said operating means to move angularly so as to release said pin after said second arm has moved said pin in a definite direction.
 10. An ignition system according to claim 6, in which said spring comprises a diaphragm which holds the hammer movable in a direction to strike the piezoelectric transducer, said engaging means being operable by the operation of said operating means to drive the hammer to the operative position of the diaphragm and to release the hammer.
 11. An ignition system according to claim 10, in which the diaphragm has a center axis directed towards the piezoelectric transducer and hoLds the hammer on the center axis.
 12. An ignition system according to claim 10, in which the engaging means comprises a pin projecting from the hammer, and a lever having an elongate slot in which said pin engages and is movable lengthwise of the slot, the lever being operatively connected with said operating means to move said pin releaseably in the driven direction of the hammer.
 13. An ignition system according to claim 10, in which said engaging means comprises a pin projecting from the hammer, and a wheel having an elongate notched groove in which said pin engages and is angularly movable to impart an angular motion to said notched groove, the wheel being operatively connected with said operating means to move said pin releasably in the driven direction of the hammer.
 14. An ignition system according to claim 1, in which said operating means comprises an angularly movable operating shaft which is connected with and drives the air compression pump and the impact generating means, respectively.
 15. An ignition system according to claim 1, in which said operating means comprises a pair of links connected with the air compression pump and the impact generating means, respectively, and a rockable operating lever operatively connected with the respective links for driving the air compression pump and the impact generating means.
 16. An ignition system according to claim 1, in which said operating means comprises a pair of arms operatively connected with the air compression pump and the impact generating means, respectively and an axially movable operating rod connected with said arms for driving the air compression pump and the impact generating means.
 17. An ignition system according to claim 1, in which the ignition nozzle comprises an injection tube having an outlet port for compressed air, and an enclosure member for covering the injection tube at a distance therefrom, the enclosure member having an outlet port positioned in front of the outlet port of the injection tube and having a suction inlet port for an ignitable fuel in the side wall thereof.
 18. An ignition system according to claim 1, in which said ignition nozzle includes an injection flow control tube mounted forwardly of the outlet end thereof.
 19. An ignition system according to claim 18, in which said injection flow control tube is made from an electrically insulating material.
 20. An ignition system according to claim 19 in which said injection flow control tube made from an electrically insulating material has a pair of discharge electrodes disposed within it. 